High-speed rail's long journey
The government plans a new high-speed rail network, from London to Birmingham and to Manchester and Leeds, known as HS2.
Ministers say it will improve the transport network and boost the economy but there has been controversy about the exact route of the line and its effect on those living near it. Here are the key points about the scheme.What is HS2?
The initial plan is for a new railway line between London and the West Midlands carrying 400m-long (1,300ft) trains with up to 1,100 seats per train.
They would operate at speeds of up to 250mph - faster than any current operating speed in Europe and would travel up to 14 times per hour in each direction.
This would be followed by a V-shaped second phase taking services from Birmingham to Manchester and Leeds. Intermediate stations in the East Midlands and South Yorkshire are also planned.What will the second phase involve?
The government's preferred route for the second phase of HS2 is a double-pronged extension linking Birmingham with Manchester and Leeds.
The route northwards from Birmingham would have five stops: Manchester, Manchester Airport, Toton in the East Midlands, Sheffield and Leeds.
A final route for phase two is expected to be chosen by the end of 2014. A proposed spur to Heathrow Airport has been put on hold pending a review of UK aviation policy, due to report in 2015.When will it open and how much will it cost?
Construction on the London-West Midlands phase was expected to begin around 2017 and open in 2026. This estimate relies on Parliament approving the necessary powers in 2015.
However, Transport Secretary Patrick McLoughlin admitted that legislation needed to build the project would not become law before the next general election.
The onward legs to Manchester and Leeds could start being built in the middle of the next decade, with the line open by 2032-33.
In June 2013 the government revised the cost of the project upwards, due to an increase in the amount of tunnelling required on the route. This took the estimated budget from £32.7bn to £42.6bn at present values - with the cost of phase one increasing from £16bn to £22bn.Could the HS2 project be delivered even quicker?
The scheme's chairman, Sir David Higgins, said building work on the northern section should be accelerated by reaching as far as Crewe by 2027, instead of aiming for Birmingham by 2026.
In a report for the government, called HS2 Plus, he said the second phase of HS2 could then be completed by 2030 instead of 2033.
Sir David also called for a more comprehensive development of HS2's London hub, Euston station.What does HS2 mean for passengers?
The Department for Transport says the project will cut Birmingham-London journey times from 1hr 21min to 49min. After the second phase, Manchester-London journeys would take 1hr 8min (down from 2hr 8min), and Birmingham-Leeds 57min (from 2hr). This would effectively reduce journey times between London and Edinburgh and Glasgow by an hour to 3hr 30min.
The government believes its creation would free up capacity on over-crowded commuter routes. It also estimates the new line could transfer 4.5 million journeys a year from the air and nine million from the roads, removing lorries from busy routes.What about fares?
There has been no announcement on ticket prices. The government says its proposals "assume a fares structure in line with that of the existing railway" and that HS2 could generate sufficient demand and revenues without needing to charge premium fares. It estimates fare revenues of up to £34bn over a 60-year period.The route of HS2 through parliamentary constituencies Why are ministers so keen on the scheme?
The government argues that Britain's rail network is reaching capacity, and that infrastructure owner Network Rail says the southern section of the West Coast Main Line - currently the quickest rail route between London and Birmingham - will be "effectively full" by 2024.
Ministers claim the London-West Midlands section alone would create around 40,000 jobs.
Groups such as the Campaign for High Speed Rail say there will be added knock-on benefits, while some MPs believe it could be a catalyst for economic growth and help rebalance the economy between the north and south.What about opposition to HS2?
HS2 will pass through around 70 parliamentary constituencies, and local groups opposed to the scheme are lobbying their MPs to vote against the plans.
There is political pressure on some Conservative MPs who will see the route pass through their constituencies, and some have indicated that they may vote against the government's bill when it reaches parliament.
Campaign group StopHS2 argues that England's north and Midlands will lose out to London, rather than benefit, and that projections do not take into account competition from conventional rail. Others object on the grounds that it will cut through picturesque countryside.